The 12-year-old girls had been plotting the murder for months, police say.

Morgan E. Geyser was allowed to have two friends over each year for her birthday. This year, she'd celebrate on May 30. That is the day she and Anissa E. Weier would try to kill their friend during a sleepover.

On Monday, the two Waukesha girls were charged in Waukesha County Circuit Court as adults with attempted first-degree intentional homicide, each facing up to 65 years in prison. Their victim, another 12-year-old from Waukesha, was stabbed 19 times by either Geyser or Weier or both, according to a criminal complaint. All three attend Horning Middle School in Waukesha.

Geyser and Weier are being held on $500,000 bail each. The pre-teens attempted murder, they told police, to pay homage to a fictional character who they believed was real after reading about him on a website devoted to horror stories.

On Saturday, a bicyclist found the victim, lying on the sidewalk and covered in blood, with injuries to her arms, legs and torso. She had managed to crawl out of the woods, where the suspects had left her. She was rushed to a hospital, where she was in stable condition Monday evening, but fighting for her life.

A Waukesha County sheriff's deputy found Geyser and Weier hours later, walking near I-94 in Waukesha. A knife with a five-inch blade was in Weier's backpack.

The Milwaukee Journal Sentinel normally does not name juveniles involved in crimes, but is naming the suspects because they are in adult court and because of the severity of the charges. A criminal complaint filed Monday detailed the allegations.

Both suspects explained the stabbing to police referencing their dedication to Slender Man, the character they discovered on a website called Creepypasta Wiki, which is devoted to horror stories.

Weier told police that Slender Man is the "leader" of Creepypasta, and in the hierarchy of that world, one must kill to show dedication. Weier said that Geyser told her they should become "proxies" of Slender Man — a paranormal figure known for his ability to create tendrils from his fingers and back — and kill their friend to prove themselves worthy of him. Weier said she was surprised by Geyser's suggestion, but also excited to prove skeptics wrong and show that Slender Man really did exist.

The suspects believed that "Slender," as Weier called him, lived in a mansion in the Nicolet National Forest in northern Wisconsin. The plan was to kill the victim and walk to Slender's mansion.

After school on Friday, Weier told police, she and Geyser went to Weier's house, where she packed a backpack with clothes, granola bars, water bottles and a picture of her mother, father and siblings. She didn't want to forget what her family looked like after leaving for Slender's mansion.

The girls then went to Geyser's house. With Geyser's father, they picked up the victim and all went to Skateland.

They came home around 9:30 p.m. and went to sleep in Geyser's room.

Geyser and Weier originally had planned to commit the murder at 2 a.m. Saturday, according to the criminal complaint. They'd duct tape their victim's mouth, stab her in the neck and pull the covers up to make it look like she was sleeping. Then they'd run.

But the plans changed after they'd been out rollerskating Friday night. Instead, they'd try to kill her in a bathroom at a nearby park the next morning. Weier knew there was a drain in the floor for the blood to go down, she told police.

'This was really happening'

The next morning, Geyser's mom said they could go and play in David's Park, on S. East Ave., just north of Les Paul Parkway. As they left, Geyser lifted up the left side of her white jacket; the knife was tucked in her waistband. Weier told police she gave Geyser a look with "wide eyes." When asked by police what that meant, Weier said, "I thought, dear God, this was really happening."

Weier said they eventually ended up in the park bathroom where Weier planned stab her friend. Once in the bathroom, Geyser handed Weier the knife, and Weier indicated that Geyser tried to restrain the victim, but Geyser had a "nervous breakdown" and Weier had to calm her down.

Weier then suggested they go for a walk, pointing out a wooded area near Rivera Drive and Big Bend Road. They could play hide and seek, distract the victim, then kill her. Geyser was the first "seeker," and Weier and the victim hid. Weier told the victim where to hide and told her to lie facedown in the dirt. The girl refused. Weier then pushed the victim and sat on her, thinking Geyser could stab her. But the victim began to yell and complain that she couldn't breathe. She was attracting attention, so Weier got off her.

Geyser gave Weier the knife, but Weier said she told Geyser she was too squeamish and gave it back.

Weier said that once Geyser got the knife back, Geyser told Weier, "I'm not going to until you tell me to." Weier said she started walking away from Geyser and then told her, "Go ballistic, go crazy." Geyser said she would go ballistic, and Weier said, "Now."

Weier said Geyser then tackled the victim and started stabbing her. The victim was screaming. Weier said when Geyser got off the victim, the victim screamed, "I hate you. I trusted you."

Weier said the victim tried to walk toward the street but was stumbling. They didn't want anyone to see her, so Weier grabbed her arm and pulled her away from the street. The victim fell. Weier said the victim couldn't breathe, see or walk. Weier told the victim to lie down and be quiet — she would lose blood more slowly. Weier told police she gave the victim those instructions so she wouldn't draw attention to herself, and so she would die. Weier told the victim they were going to get her help; but they never planned on actually doing so. They hoped she would die, and they would see Slender and know he existed. With the victim lying on the ground, they began to back away.

When police asked Weier if she knew what it meant to kill someone, Weier said, "I believe it's ending a life and I regret it." Weier also said, "The bad part of me wanted her to die, the good part of me wanted her to live."

'I didn't feel remorse'

Geyser's report to police was much shorter.

She confirmed the details of Weier's interview with law enforcement officials, but said she thought that Weier stabbed the victim first.

"Weier put the knife in my hand and then I continued to stab her," the complaint quoted Geyser.

When asked how many times Geyser thought she stabbed the victim, Geyser said she did not know; all she heard was screaming.

At one point, when talking with police, Geyser said she was sorry. She said she had put the knife back into her bag and wiped it off on her jacket. She then told a detective, "It was weird that I didn't feel remorse."

Geyser said they had to do it or "he would kill our family." When asked who "he" was, Geyser said she didn't know him. When asked what she was trying to do when she stabbed her friend, Geyser said, "I may as well just say it: Kill her."

When asked about Slender Man, Geyser said she had never met him but said he watches her and he can read minds and teleport. Geyser said what she did was "probably wrong." She asked a detective if it is illegal to stab someone in self-defense. The detective said sometimes, and asked her if that was what happened in this instance.

No, she said.

In court on Monday, Geyser's family members broke into tears several times during her appearance.

"The family is very horrified at what has happened," attorney Donna Kuchler said.

Waukesha County District Attorney Brad Schimel stressed the girls were innocent until proven guilty, but added he has never encountered allegations like this as a prosecutor.

"Most of the time in a crime like this, with such violence like this, there's spur of the moment, there's the heat of passion," he said.

This time, he said, it was calculated.

"It's troubling when a person lashes out in anger," he said. "It's more troubling when they lash out in cold blood. Isn't that the worst kind of killer, the cold-blooded killer?"

Schimel, a Republican running for state attorney general, said he had to bring the case in adult court because of the level of charges against the girls. He said he expected the girls' attorneys to attempt to "reverse waive" them into juvenile court, which he said he would resist.

If moved into juvenile court and convicted, the girls could be held at most until they were 25 years old, Schimel said.

"It's a very shocking incident. There's no two ways about it," Schimel said.Morgan Geyser